The Gate Driver On Array (GOA) is an important means for realizing narrowing of a bezel of a display apparatus. In general, a GOA is composed of multiple stages of shift register (sometimes referred to as SR hereinafter) units, and various stages of shift register units sequentially shift to output a scanning pulse to gates of thin film transistors in each row of pixel units, so that the corresponding thin film transistors are turned on to realize a process of driving each row of pixel units.